Low power battery supervisory circuit with adaptive battery health monitor

Author

Inhee Lee ; Yoonmyung Lee ; Sylvester, Dennis ; Blaauw, D.

Author_Institution

Univ. of Michigan, Ann Arbor, MI, USA

fYear

2014

fDate

10-13 June 2014

Firstpage

1

Lastpage

2

Abstract

We propose a battery supervisory circuit (BSC) for wireless sensor nodes that automatically adapts to varying battery health, as reflected by its internal resistance (R_BAT), and establishes a constant effective threshold voltage. Compared to a conventional fixed-threshold BSC, the new design avoids oscillation and widens the usable range of battery voltages, independent of R_BAT. R_BAT is measured by inducing a test current using decaps and measuring the resulting battery RC response time. When tested with a 2μAh battery and 11μA sensor system, the BSC reduces the required hysteresis from 656mV to 77mV, increasing the usable battery voltage range by 2.7×.

Keywords

RC circuits; low-power electronics; reference circuits; wireless sensor networks; RC response time; adaptive battery health monitor; current 11 muA; internal resistance; low power battery supervisory circuit; voltage 656 mV to 77 mV; wireless sensor nodes; Batteries; Battery charge measurement; Delays; Generators; Monitoring; Temperature measurement; Threshold voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

VLSI Circuits Digest of Technical Papers, 2014 Symposium on

Conference_Location

Honolulu, HI

Print_ISBN

978-1-4799-3327-3

Type

conf

DOI

10.1109/VLSIC.2014.6858363

Filename

6858363